A camera recording video or still images commonly focuses upon only a portion of a given area of an entire, 360 degree span of visual scene information present in the physical world encompassing the camera. Field of view and “angle of view” (AOV) are terms commonly used to describe an angular extent of a given subset scene of an entirety of a surrounding scene from which image data is captured by a given camera as a function of its lensing system and its image data acquisition system.
Angles of view may vary widely between different cameras due to differences in deployed lens systems and imaging system attributes. For example, arrays of digital sensors are usually smaller than 35 mm film, and this causes a lens to have a narrower angle of view than with 35 mm film, by a constant factor for each sensor. Accordingly, gauging or estimating the angle of view for a given camera is generally impractical without engaging and using a viewfinder of the camera, for example by directly looking into a viewfinder or by viewing streaming data provided by the camera on a video monitor or other graphic display device.